31107

Appears in sequences

• a(n) = a(n-2) + a(n-3), with a(0) = 0, a(1) = 1, a(2) = 4.at n=36A007309
• Number of ordered triples (i,j,k) with |i| + |j| + |k| <= n and gcd(i,j,k) <= 1.at n=30A100450
• a(n) = number of n-lettered words in the alphabet {1, 2, 3} with as many occurrences of the substring (consecutive subword) [1, 1, 2] as of [1, 1, 3].at n=10A211288
• Generalized Markoff numbers: largest of 7-tuple of positive numbers a, b, c, d, e, f, g satisfying the Markoff(7) equation a^2+b^2+c^2+d^2+e^2+f^2+g^2 = 3abcdefg.at n=35A227211
• Composites whose prime factorization in base 12 is an anagram of the number in base 12.at n=17A260055
• Expansion of Product_{k>=1} (1 - x^(10*k))/(1 - x^k).at n=40A261776
• a(n) is the number of terms in row n of the array A378303.at n=25A378307